(1) Field of the Invention
The present invention relates to a multilayered cosmetic container obtained by covering an opaque or translucent hollow inner container with a transparent or translucent outer layer.
The present invention may be utilized in a molded product obtained by covering the opaque or translucent hollow inner container with a transparent or translucent transmissive outer layer.
(2) Description of Related Art Including Information Disclosed Under 37 CFR 1.97 and 1.98
Japanese Patent No. 4377447 discloses a multilayered cosmetic container obtained by covering (hereinafter, over-molding) an opaque or translucent hollow inner container with a transparent or translucent transmissive outer layer. In this type of container, strength of an entire container is improved by an outer layer protecting the hollow inner container, and in addition, decoration property is excellent by an expression of a unique appearance obtained by a pattern of the hollow inner container seen through the transmissive outer layer. Therefore, this is used as the cosmetic product container in which durability and the appearance are important.
However, in a process of manufacturing the multilayered cosmetic container in which the hollow inner container made of a synthetic resin with a hollow inner portion including a neck portion, which forms an opening, a body portion with a diameter larger than that of the neck portion, and a shoulder portion, which connects the body portion to the neck portion, is over-molded with the outer layer formed by injection of a melting resin on an outer side of the hollow inner container except a part of the neck portion or an entire neck portion, or the entire neck portion and a part of the shoulder portion, rigidity of the hollow inner container is not necessarily sufficient when forming the outer layer, so that there is a problem that the hollow inner container is crushed or deformed due to slight change in pressure and temperature.
Especially, the melting resin, which flows from the body portion to the shoulder portion, stagnates or a disturbed flow thereof is generated on a portion on which a flowing direction changes, that is to say, on a shoulder tip and a bottom corner portion, so that the pressure applied to the hollow inner container and a resin temperature likely change, and as a result, the corner portion of the hollow inner container and a periphery thereof are prone to be crushed.
As a countermeasure against this, it is effective to keep a flow rate and the pressure of the melting resin when forming the outer layer constant as far as possible by making a curvature of the outer layer, which covers the corner portion of the hollow inner container, the same as the curvature of the corner portion of the hollow inner container and by making a thickness of the outer layer uniform over an area as wide as possible along a shape of the hollow inner container.
However, with such a shape, there is a case in which a color of the corner portion, especially the shoulder tip of the hollow inner container, which is seen through the outer layer, appears in a light color highlighted against the color of a peripheral portion, which should essentially appear in the same color, according to a principle to be describer later. Then, a boundary between a portion, which appears in the light color, and a portion, which does not appear in the light color, is seen as a shadow of a cosmetic product filled in the container, so that there is a case in which, even when the cosmetic product is used and the contents are reduced actually, an appearance causes misunderstanding that the contents are always left to the shoulder tip.
An object of the present invention is to provide a structure capable of stably forming the multilayered cosmetic container having a specific shape with the outer layer of the multilayered cosmetic container relatively thin and without crushing the hollow inner container while inhibiting a phenomenon that the color of the corner portion of the hollow inner container appears to change by light, which passes through the transparent or translucent outer layer.